2 chiyanneru multiplex transmission modes null of terebijiyon

摘要

PURPOSE:To transmit a 2-channel NTSC color television signal through a one- channel NTSC transmission line by extracting alternately two luminance signals and two chrominance signals after time base compression, multiplexing and transmitting them. CONSTITUTION:Signals of two programs 1, 2 are separated into luminance signals Y1, Y2 and chrominance signals C1, C2 by two YC separating circuits 1, 2 respectively. Line/field subsamplers 3, 4 sample the luminance signals Y1, Y2 according to output moving modes M1, M2 of detectors 5, 6 detecting moving information of the programs 1, 2. The output is subjected to time compression by time base compressors 7, 8, selected by a switch S1 to form a luminance signal Y multiplexed with the luminance signals Y1, Y2. The chrominance signals C1, C2 are added to the luminance signal Y while being switched at each field by a switch S2. Further, the moving modes M1, M2, a synchronizing signal and a color burst are added by an adder circuit 9 and the result is sent to the NTSC transmission line as a signal NT.